Xantrex 804-1220-02 TRUECharge2 12V 20A Parallel Stackable Battery Charger Microprocessor-controlled, multistage charging algorithms Settings for two and three-stage charging Settings for flooded, gel, agm or lead-calcium batteries Auto-ranging universal Input voltage (90-265 VAC, 47-63 Hz) is also Compatible with a generator or other low-quality power sources Temperature-compensated charging